The present invention relates to an image processing apparatus and an image processing method which perform image processing with respect to an input color image in, for example, a digital color copying machine which reads a color image on a document and forms a reproduced image.
In general, a color copying machine separates the colors of a color image on a document by using, e.g., a color line CCD sensor, reads this image, converts the read image into a signal for a color material such as a color toner or a color ink, and prints according to this signal. This conversion is referred to as color conversion in this specification.
In color conversion, color separation signals R (red), G (green) and B (blue) are subjected to a predetermined calculation and thereby converted into color material signals C (cyan), M (magenta) and Y (yellow).
In such a color copying machine, the color image signals R, G and B are conventionally used to determine whether each remarked pixel is part of a character or a line drawing.
However, since image segmentation is carried out by using color image signals R, G and B having high resolution, the possibility of occurrence of an identification error of black characters/line art due to color shift is high, and image segmentation with high accuracy is difficult.